This invention relates to one shot multivibrator circuits, and more particularly, it relates to a one shot multivibrator circuit particularly adapted for manufacture by FET techniques such as MOS LSI techniques.
The threshold voltage of FET devices is dependent upon processing parameters which are difficult to control. For example, the surface charge density, surface contamination, doping levels, etc., all are difficult to control in the manufacture of MOS LSI devices. Yet each of these parameters of the finished device affects the threshold voltage of the finished device. The prior art one shot multivibrator circuits are turned "on" and "off" when a control signal first exceeds and then drops below a threshold voltage of the MOS device used in the circuit. Accordingly, if the threshold voltage of the various FET transistors can vary by as much as 33 percent due to the processing parameters which are difficult to control, the output pulse width can also vary within wide limits.